I think the point that Taildragger67 is making when referring to the O'Hare accident is that the crew can be completely exonerated (ie, 0% fault) even when there was something they could have done to avoid the accident. The fact that something could have been done does not necessarily mean that the crew must get "a little bit" of the blame. For example, the fact that the O'Hare accident would not have occurred if the crew had not throttled back does not make it "Airline 99.9% / Crew 0.01%".
(The O'Hare accident was the airline's fault, wasn't it? I'm aware that the manufacturer was blamed initially, for a defective bolt, with the result that all AirNZs DC10s were grounded for several weeks. But I seem to recall that the bolt was found to have nothing to with it.)